JP4584107B2 - Cooling storage - Google Patents

Description

The present invention comprises a plurality of evaporators, relates to a cooling storage cabinet for supplying the refrigerant from one compressor to them.

  As this type of cooling storage, for example, a freezing compartment and a refrigeration compartment are insulated and formed in a heat-insulating storage body, and an evaporator is disposed in each chamber, and each evaporator is provided with a single compressor. One in which a coolant is alternately supplied to cause a cooling action is known. For example, Patent Document 1 can be exemplified.

  In this system, the refrigerant is compressed by a compressor and liquefied by a condenser, and this is alternately supplied to a freezer evaporator and a refrigerator refrigerator connected to the outlet side of the three-way valve via a capillary tube, respectively. In the so-called control operation in which the normal cooling operation is performed in the temperature range close to the set temperature, for example, when the chamber on the cooling side reaches the OFF temperature, the three-way valve is switched and the other side is switched. The compressor is switched to the chamber cooling mode, and the compressor is stopped when both of the detected temperatures in the chambers are lower than the OFF temperature.

  With this configuration, when the user stores food with high temperature in one storage room during the above control operation, the storage room should be sufficiently cooled before the other storage room is cooled. Therefore, there is an advantage that the newly contained food can be sufficiently cooled.

  However, in the above configuration, when food having a high temperature is accommodated in both storage rooms, the storage room that is cooled first is good, but the temperature of the food does not drop easily in the storage room that is cooled thereafter. There is a problem.

In response to such a case, for example, Patent Document 2 proposes a technique in which a control device alternately switches both storage chambers at a predetermined time ratio. Here, for example, when both the temperature of the storage room of the refrigerator compartment and the freezer compartment exceed the ON temperature, the cooling of the refrigerator compartment and the cooling of the refrigerator compartment are alternately switched at a ratio of, for example, 30 minutes: 20 minutes. When the mode is executed and the temperature of the freezer compartment still rises due to insufficient cooling capacity, when the freezer compartment reaches a predetermined temperature (for example, −12 ° C.), the time ratio is set to the freezer compartment side. Has been changed to a time ratio (for example, 40 minutes: 20 minutes) to prioritize the increase in the freezer compartment temperature.
Japanese Utility Model Publication No. 60-188982 JP 2002-22336 A

  However, even with the above-described configuration, for example, after food having a high temperature is stored in the freezer compartment and the indoor temperature exceeds the ON temperature and the freezer compartment cooling mode is entered, the refrigerator compartment door is frequently opened and closed this time. If the room temperature temporarily exceeds the ON temperature even temporarily, it will immediately shift to the alternate cooling mode. Then, since a part of the freezing capacity is devoted to the cooling of the refrigerator compartment, the cooling of the freezer compartment is delayed, and eventually the temperature rise of the freezer compartment cannot be sufficiently suppressed.

  In addition, when performing the so-called pull-down operation in which the storage room temperature is cooled from the state close to room temperature to the set temperature instead of the normal control operation, when the alternate cooling mode in the long cycle of 30 minutes: 20 minutes described above is performed, The operation of cooling the storage room temperature with a predetermined temperature curve cannot be performed, and the cooling performance varies depending on the specifications such as the volume of the storage body. However, if the switching in the alternate cooling mode is performed in a short cycle such as 3 minutes: 2 minutes, even if it is desired to cool the freezing room rapidly as described above, the ability to cool the refrigerating room is divided. The problem becomes more pronounced and undesirable.

  The present invention has been completed based on the above circumstances, and selectively supplies refrigerant from a single compressor to a plurality of evaporators provided in a plurality of storage chambers having different thermal loads. In such a cooling storage, it is possible to prevent unnecessarily shifting to the alternate cooling mode when one of the storage rooms is in the cooling mode, and to perform a pull-down operation with a predetermined temperature curve. The aim is to provide a possible cold storage.

The control method for achieving the above object can be implemented by a cooling storage having the following configuration (invention of claim 1 ).

A refrigeration cycle having the following configurations A1 to A6;
(A1) Compressor for compressing refrigerant (A2) A condenser (A3) for releasing heat from the refrigerant compressed by the compressor is connected to the condenser side, and two outlets are first and second refrigerants A valve device (A4) connected to the supply path and capable of selectively switching the inlet side to either the first or second refrigerant supply path; and the first and second refrigerant supply paths. First and second evaporators (A5) provided to each of the throttle devices (A6) for restricting the refrigerant flowing into each evaporator from the refrigerant outlet side of the first and second evaporators to the refrigerant suction side of the compressor A storage body having first and second storage chambers, each of which has a different thermal load and is cooled by cold air generated by the first and second evaporators;
A target temperature setter for setting a target temperature in each of the first and second storage chambers;
First and second temperature sensors for detecting the internal temperature in each storage chamber;
A temperature deviation calculating means for calculating, for each storage room, a temperature deviation which is a difference between each target temperature set in the target temperature setter and each storage room temperature detected by each temperature sensor; ,
An inter-room temperature deviation integrating means for calculating an inter-room temperature deviation which is a difference for each storage room with respect to the temperature deviation calculated by the temperature deviation calculating means, and integrating this;
The cooling storage is provided with valve control means for changing the open ratio of the first and second refrigerant supply passages in the valve device by comparing the integrated value integrated by the room temperature deviation integrating means with a reference value.

Moreover, it is also possible to comprise as a cooling storage warehouse provided with the following structure (invention of Claim 2 ).

A refrigeration cycle having the following configurations A1 to A6;
(A1) Compressor driven by an inverter motor to compress refrigerant (A2) A condenser (A3) for releasing heat from the refrigerant compressed by this compressor is connected to the condenser side and two outlets are first And a valve device (A4) that is connected to the second refrigerant supply path and selectively allows the inlet side to communicate with either the first or second refrigerant supply path. The first and second evaporators (A5) respectively provided in the refrigerant supply passages of the first and second evaporators (A5) A throttling device (A6) for restricting the refrigerant flowing into the respective evaporators from the refrigerant outlet side of the first and second evaporators to the compressor A refrigerant main body having first and second storage chambers that have different thermal loads and are cooled by cold air generated by the first and second evaporators;
A target temperature setter for setting a target temperature in each of the first and second storage chambers;
First and second temperature sensors for detecting the internal temperature in each storage chamber;
A temperature deviation calculating means for calculating, for each storage room, a temperature deviation which is a difference between each target temperature set in the target temperature setter and each storage room temperature detected by each temperature sensor; ,
An inter-room temperature deviation integrating means for calculating an inter-room temperature deviation which is a difference for each storage room with respect to the temperature deviation calculated by the temperature deviation calculating means, and integrating this;
A valve control means for changing the open ratio of the first and second refrigerant supply paths in the valve device by comparing the integrated value integrated by the inter-room temperature deviation integrating means with a reference value;
A temperature deviation cumulative value calculating means for calculating a temperature deviation cumulative value that is a cumulative value of the sum for each storage room with respect to the temperature deviation calculated by the temperature deviation calculating means;
The cooling storage is provided with rotation speed control means for changing the rotation speed of the inverter motor by comparing the accumulated value calculated by the temperature deviation accumulated value calculation means with a reference value.

Further, in the cooling storage according to claim 1 or 2 , when the valve control means increases the open ratio of the refrigerant supply path of one storage chamber, the internal temperature of the other storage chamber is higher than the set temperature. The temperature may be within a temperature range that is higher by a predetermined value (Invention of Claim 3 ). In that case, the internal temperature of one of the storage chambers is equal to or higher than a temperature that is higher than the set temperature by a predetermined value. It may be a condition that the state continues for a predetermined time (the invention of claim 4 ).

Furthermore, the target temperature setter may be configured to sequentially output different target temperatures over time (invention of claim 5 ). In this case, the target temperature setter includes a storage unit that stores a function that represents a temporal change mode of the target temperature, and a target that reads the function stored in the storage unit and calculates the target temperature as time passes. A temperature calculating means may be provided (the invention of claim 6 ), or a storage means for storing a temporal change mode of the target temperature as a reference table in which the temperature and the elapsed time are contrasted, and the passage of time. It is good also as a structure provided with the table reading means which reads the target temperature in a memory | storage means collectively (invention of Claim 7 ).

  According to the present invention, the ratio of the refrigerant supply time to each of the first and second evaporators is the target temperature set in each of the first and second storage chambers and the actual storage measured in each storage chamber. Control is not based on the deviation from the internal temperature, but is based on the integrated value obtained by integrating the differences between the deviations. For example, when the door is temporarily opened and the outside air flows into the storage chamber, Even if the internal temperature rises temporarily, there is no sudden change in the integrated value of the temperature deviation, so that it is possible to prevent unnecessary transition to the alternate cooling mode when the one storage chamber is in the cooling mode. . In addition, since the alternate cooling mode can be repeated in a short cycle, it is possible to provide a cooling storage and its operation method that enables a pull-down operation to be performed with a predetermined temperature curve.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. In this Embodiment 1, the case where it applies to the horizontal type | mold (table type) refrigerator-freezer for business is illustrated, First, FIG. 1 demonstrates the whole structure. Reference numeral 10 denotes a storage body, which is composed of a horizontally long heat insulating box opened on the front surface and supported by legs 11 provided at the four corners of the bottom surface. The inside of the storage body 10 is divided into left and right by a heat insulating partition wall 12 to be attached later, the left relatively narrow side is a freezer compartment 13F corresponding to the first storage room, the right wide side is the second It is a refrigerator compartment 13R corresponding to a storage room. Although not shown, a swinging heat insulating door is detachably attached to the front opening of the freezer compartment 13F and the refrigerator compartment 13R.

  A machine room 14 is provided on the left side as viewed from the front of the storage body 10. An evaporator room 15 for the heat-insulating freezer compartment 13F communicating with the freezer compartment 13F is formed overhanging at the upper back side in the machine room 14, and a duct 15A and an evaporator fan 15B are provided here. In addition, a compressor unit 16 is housed in the lower part of the compressor unit 16 so that it can be taken in and out. In addition, an evaporator chamber 18 for the refrigerator compartment 13R is formed on the surface of the partition wall 12 on the refrigerator compartment 13R side by extending a duct 17, and an evaporator fan 18A is provided here.

  The compressor unit 16 has a compressor 20 that is driven at a constant speed by a motor (not shown) to compress refrigerant, and a condenser 21 that is connected to the refrigerant discharge side of the compressor 20 on a base 19. A condenser fan 22 (shown only in FIG. 2) for air-cooling the condenser 21 is also mounted.

  As shown in FIG. 2, the outlet side of the condenser 21 is connected through a dryer 23 to an inlet 24 </ b> A of a three-way valve 24 that is a valve device. The three-way valve 24 has one inlet 24A and two outlets 24B and 24C, and each outlet 24B and 24C is connected to the first and second refrigerant supply paths 25F and 25R. The three-way valve 24 can perform a flow path switching operation for selectively communicating the inlet 24A with one of the first and second refrigerant supply paths 25F and 25R.

  In the first refrigerant supply path 25F, a freezer compartment capillary tube 26F corresponding to a throttling device and a freezer compartment evaporator (first evaporator) 27F accommodated in the evaporator compartment 15 on the freezer compartment 13F side. And are provided. The second refrigerant supply path 25R includes a capillary tube 26R on the refrigerator compartment side, which is also a throttling device, and an evaporator (second evaporator) accommodated in the evaporator chamber 18 on the refrigerator compartment 13R side. ) 27R. The refrigerant outlets of both the coolers 27F and 27R are connected in series with the accumulator 28F, the check valve 29 and the accumulator 28R, and branch from the downstream side of the check valve 29 to the suction side of the compressor 20. A refrigerant circulation channel 31 is provided. The refrigerant circulation path returning from the discharge side to the suction side of the compressor 20 described above constitutes a well-known refrigeration cycle 40 that supplies refrigerant to the two evaporators 27F and 27R by one compressor 20. The supply destination of the liquid refrigerant can be changed by the valve 24.

The compressor 20 and the three-way valve 24 are controlled by a refrigeration cycle control circuit 50 having a built-in CPU. The refrigeration cycle control circuit 50 includes a temperature sensor 51F corresponding to a first temperature sensor for detecting the air temperature in the freezer compartment 13F and a temperature corresponding to a second temperature sensor for detecting the air temperature in the refrigerator compartment 13R. A signal from the sensor 51R is given. On the other hand, a target temperature setter 55 is provided, and the user can set the target temperatures of the freezer compartment 13F and the refrigerator compartment 13R here, and the target temperatures of the storage chambers 13F, 13R according to the setting operation. Along with TFa and TRa, upper limit set temperatures TF (ON) and TR (ON) and lower limit set temperatures TF (OFF) and TR ( OFF ) are determined, and signals corresponding to these are given to the refrigeration cycle control circuit 50.

  In the refrigeration cycle control circuit 50, the detected temperature TF of the temperature sensor 51F is higher than the upper limit set temperature TF (ON) of the freezer compartment 13F, or the detected temperature TR of the temperature sensor 51R is the upper limit set temperature TR (ON) of the refrigerator compartment 13R. ), The compressor 20 is started to start the cooling operation, and the detected temperatures TF and TR are both lower limit set temperatures TF (OFF) and TR (OFF) of the freezer compartment 13F and the refrigerator compartment 13R, respectively. ), The operation of the compressor 20 is stopped.

Moreover, the difference in the refrigerating cycle control circuit 50, and the target temperature TFa of the freezing room 13F set in the target temperature setter 55, the actual internal temperature TF of the detected freezer compartment 13 F by a temperature sensor 51F ( calculates the F room temperature deviation ΔTF a TF-TFA), the target temperature setter 55 and the target temperature TRa of the refrigeration room 13R set in, the temperature sensor 51R is detected by the refrigerating compartment 13 actually in the refrigerator of R A temperature deviation calculating means 56 is provided for calculating an R room temperature deviation ΔTR which is a difference (TR−TRA) from the temperature TR. In addition, for each of the calculated temperature deviations ΔTF, ΔTR, a “room temperature deviation” that is a difference (ΔTR−ΔTF) is calculated, and the “room temperature deviation” is integrated for a predetermined time (for example, 5 minutes). An inter-room temperature deviation integrating means 57 is also provided. The valve control means 58 controls the opening ratio of the first and second refrigerant supply paths 25F and 25R in the three-way valve 24 in accordance with the value accumulated by the inter-room temperature deviation integrating means 57. ing. Specifically, the opening ratio of the two refrigerant supply paths 25F and 25R is set to 3: 7 as an initial value of a ratio of R (second refrigerant supply path 25R): F (first refrigerant supply path 25F). That is, the time ratio (R room cooling time ratio) during which the refrigerator compartment 13R is cooled is 0.3, and the R room cooling time ratio is set to 0.1 in 0.1 increments. It can be changed in the range of 1 to 0.9. The temperature deviation calculating means 56, the inter-room temperature deviation integrating means 57, and the valve control means 58 are configured by software executed by the CPU, and specific control modes thereof are shown in FIGS. This is as shown in the flowchart and will be described next together with the operation of this embodiment.

  When the power is turned on and the target temperature setter 55 sets the target temperatures TFa and TRa, the compressor 20 is started, and first, the control flow of “R room F room cooling time control” shown in FIG. 3 is started. The First, the integrated value B is initialized (step S11), and the deviation (R between the actual internal temperature TR of the R room (refrigeration room 13R) given from the R room sensor 51R and the target temperature TR of the R room at that time (R11). (Room temperature deviation) ΔTR is calculated (step S12). Next, the actual internal temperature TF of the F room (freezing room 13F) given from the F room sensor 51F at that time, the target temperature TF of the F room, and Deviation (F room temperature deviation) ΔTF is calculated (step S13). Then, the "room temperature deviation" (ΔTR-ΔTF), which is the difference between the storage chambers 13F, 13R of the temperature deviations ΔTF, ΔTR of the respective storage chambers 13F, 13R obtained here, is calculated and integrated. Integration is performed as B (step S14), and it is determined whether or not one cycle determined at the predetermined time in step S15 has been completed. If not completed, steps S12 to S14 are repeated until the cycle is completed. The value B is calculated.

  Next, the integrated value B calculated in step S15 is compared with the two upper limit reference values L_UP and the lower limit reference value L_DOWN (step S16). If the integrated value B is greater than the upper limit reference value L_UP, the R room temperature Since this means that the integrated value of the deviation ΔTR is considerably large, the R chamber cooling time ratio RR is increased from the initial value of 0.3 by one step (0.1) (step S17), and the integrated value B is the lower limit reference If the value is smaller than the value L_DOWN, it means that the integrated value of the R room temperature deviation ΔTR is small and conversely the F room temperature temperature deviation ΔTF is considerably large. Therefore, the R room cooling time ratio RR is changed from the initial value of 0.3 to 1. Decrease by step (0.1) (step S18), initialize integrated value B (step S19), and return to step S12. If the integrated value B is between the upper limit reference value L_UP and the lower limit reference value L_DOWN, the process returns to step S12 without changing the R chamber cooling time ratio RR.

  When integrated value B is determined as described above, the control flow of “R room F room switching cooling control” shown in FIG. 4 is then executed. Here, first, the value ts of the cycle elapsed time timer is reset (step S21), and the three-way valve 24 is first switched to open the refrigerating chamber 13R side (second refrigerant flow path 25R side) (step S22). It is determined whether or not the cooling time has ended (step S23), and steps S22 to S23 are repeated until the time ends to cool the refrigerator compartment 13R. The R chamber cooling time is calculated by multiplying a predetermined cycle To (for example, 5 minutes) by the R chamber cooling time ratio RR described above.

  When the value ts of the cycle elapsed time timer becomes equal to or greater than the value obtained by multiplying the period To by the R chamber cooling time ratio RR (To × RR), the three-way valve 24 is now on the freezer compartment 13F side (first refrigerant flow path). 25F side) is opened (step S24), and steps S24 to S25 are repeated until the period To elapses to cool the freezer compartment 13F. When the period To elapses, the process returns to step S21 and the above cycle is repeated. Is repeated. As a result, for example, the refrigeration room 13R and the freezing room 13F are alternately cooled while a 1/5 period To elapses, and the ratio of the cooling time is determined by the R room cooling time ratio RR. It will be.

  The alternate cooling mode in which the freezer compartment 13F and the refrigerator compartment 13R are alternately cooled is executed until both the storage compartments 13F, 13R are both below the lower limit set temperatures TF (OFF), TR (OFF) ( Pull-down operation). As a result, when the storage chambers 13F and 13R are both cooled to around the set temperature, the normal control operation is performed, and thereafter, the detected temperatures TF and TR in the storage chambers of the storage chambers 13F and 13R are set to their upper limits. When the temperature becomes higher than the temperature TF (ON) and the upper limit set temperature TR (ON), the operation of the compressor 20 is resumed and the storage chamber is shifted to the cooling mode. In addition, for example, when the refrigerator compartment 13R is in the refrigerator compartment cooling mode in which the refrigerator compartment 13R is cooled and the detected temperature TF of the freezer compartment 13F exceeds the upper limit set temperature TF (ON), both the storage compartments 13F and 13R are alternately cooled. Transition to alternate cooling mode.

  Here, when the ratio of the refrigerant supply time to the refrigerator compartment 13R and the freezer compartment 13F is determined, the deviations ΔTF and ΔTR between the target temperatures of the storage chambers 13R and 13F and the actual internal temperature are simply monitored, When the storage chamber with the larger deviations ΔTF and ΔTR is controlled to cool for a longer time, for example, the door of the storage chamber is opened and the outside air flows into the storage chamber, so that the inside temperature is temporarily reduced. When the temperature rises, the refrigerant supply to the storage room immediately increases, so that the cooling proceeds even though the door is closed and the internal temperature tends to return, and the storage room is excessively cooled. There is a concern that On the other hand, according to this embodiment, the difference between the deviations ΔTF and ΔTR is taken and controlled based on the integrated value B obtained by further integrating them, so that the internal temperature has temporarily increased. However, since there is no sudden change in the integrated value B of the temperature deviation, the cooling ratio is not unnecessarily changed, and the cooling control is stabilized.

<Embodiment 2>
In the first embodiment described above, the target temperature setter 55 outputs signals corresponding to constant lower limit set temperatures TF (OFF) and TR (OFF) that do not change with time, and the internal temperature of the storage chambers 13F and 13R. In the pull-down operation that cools the room temperature from the room temperature range to the vicinity of each set temperature, and in the control operation that maintains the internal temperature at the set temperature after that, the constant set temperature is controlled to the target. In the second embodiment, the target temperature setter is configured to sequentially output different target temperatures as time passes (embodiment of the invention of claim 5 ).

That is, each target temperature of the freezer compartment 13F and the refrigerator compartment 13R is given as its change with time (that is, how the target temperature is changed with time t). Of the target temperature during the control operation for cooling the stored product to the set temperature set by the user, and the set temperature during the control operation, for example, when the power is turned on for the first time after installing this refrigerator-freezer There are two types of change modes of the target temperature in the so-called pull-down cooling operation in which cooling is performed from a considerably high temperature to a temperature range during the control operation, and both of these change modes are performed for each freezer compartment 13F and refrigerator compartment 13R. It is expressed by a function with t as a variable, and the function is stored in a storage means constituted by EPROM or the like. Come, it may be configured to calculate the target temperature combined function stored in the storage means over reads time by a CPU or the like (embodiment of the invention of claim 6). In the second embodiment, other configurations are the same as those in the first embodiment.

  When the target temperature setter is configured to sequentially output different target temperatures as time elapses as in the second embodiment, for example, target curves R and F of the temperature to be cooled are drawn as shown by broken lines in FIG. Can do. When the storage chambers 13F and 13R are alternately cooled under the two target curves as described above, the internal temperature of the refrigerator compartment 13R and the internal temperature of the freezer compartment 13F are indicated by solid lines R and F in the same figure. Change. FIG. 6 shows an example in which the refrigeration capacity of the refrigeration cycle 40 is insufficient to pull down both the storage chambers 13F and 13R simultaneously according to the target curve. FIG. 6 shows that the refrigeration capacity is excessive. It shows a case. In any case, however, even if there is such a shortage or excess of capacity, both the storage chambers 13F and 13R are cooled in a well-balanced manner without causing only one storage chamber to be overcooled or insufficiently cooled. be able to.

<Embodiment 3>
In the first and second embodiments, the example in which the constant speed type compressor 20 is used is shown. However, the compressor 20 is a variable speed type driven by an inverter motor, and thereby the refrigeration cycle. You may be able to adjust 40 abilities. The embodiment will be described as a third embodiment with reference to FIGS.

This embodiment is different from the first and second embodiments in that the compressor 20 is driven by an inverter motor. The rotation speed of the inverter motor of the compressor 20 is controlled by, for example, a rotation speed control means 60 that includes an inverter and outputs alternating current of variable frequency, and the rotation speed control means 60 receives a signal from the temperature deviation accumulated value calculation means 70. Given. As in the second embodiment, the target temperature setter 80 is configured to sequentially output different target temperatures with the passage of time (the embodiment of the invention of claim 5 ), and the other points are the same as in the first embodiment. Therefore, the same reference numerals are given to the same parts.

  In the target temperature setting device 80 of the third embodiment, as described above, the target temperatures of the freezer compartment 13F and the refrigerator compartment 13R change with time (that is, the target temperature changes with time t). As a change mode of the target temperature, a change mode of the target temperature at the time of control operation for cooling a stored product such as food to a set temperature set by the user, for example, installing this refrigerator-freezer Like when the power is turned on for the first time, there are two types of changes in the target temperature during the so-called pull-down cooling operation in which cooling is performed from a temperature considerably higher than the set temperature during the control operation to the temperature range during the control operation. Each change mode is expressed by a function with time t as a variable for each freezer compartment 13F and refrigerator compartment 13R. Stored in the storage unit 81 constituted by example, if EPROM or the like. For example, the functions TFa = fF (t) and TRa = fR (t) indicating the change modes of the target temperatures TFa and TRa of the freezer 13F and the freezer 13R during the pull-down cooling operation are represented by the graph shown in FIG. The thing can be illustrated.

  The two target temperatures TFa and TRa from the target temperature setter 80 are given to the temperature deviation calculating means 56 together with the two internal temperatures TF and TR obtained from the temperature sensors 51F and 51R, respectively, where each temperature deviation ΔTF = (TF-TFa) and .DELTA.TR = (TR-TRa) are calculated. The values of the temperature deviations ΔTF and ΔTR are given to the inter-room temperature deviation integrating means 57 and the temperature deviation accumulated value calculating means 70 in the next stage. The control in the inter-chamber temperature deviation integrating means 57 is the same as in the first embodiment, and the three-way valve 24 is controlled based on the integrated value B, whereby the refrigerator compartment 13R and the freezer compartment 13F are alternately cooled. The ratio of the cooling time is determined by the R chamber cooling time ratio RR.

  On the other hand, in the temperature deviation accumulated value calculation means 70, the following control is performed to determine the rotation speed of the inverter motor that drives the compressor 20.

  That is, for example, for 2 minutes to 10 minutes (5 minutes in this embodiment), both deviations ΔTR and ΔTF are added together and integrated, and the value is given to the rotation speed control means 60. The rotation speed control means 60 compares the accumulated value A of the deviation with a predetermined reference value (lower limit value and upper limit value). When the accumulated value A is larger than the upper limit value L_UP, the rotation speed of the inverter motor is increased. When the integrated value A is smaller than the lower limit value L_DOWN, the rotational speed of the inverter motor is decreased. Note that the functions of the temperature deviation accumulated value calculating means 70 and the rotation speed control means 60 described above are realized by software executed by the CPU, and the processing procedure of the software is as shown in FIG.

The software configuration will be described with reference to FIG. When the compressor rotation control start routine is started by the CPU (step S31), the accumulated value A is first initialized to, for example, 0 (step S32). Next, the target temperature setter 80 reads out a predetermined function from the storage means 81, and substitutes a variable t (elapsed time from the start of this routine) into the function, so that each target temperature of the refrigerator compartment 13R and the freezer compartment 13F is obtained. TRa and TFa are calculated respectively (steps S33 and S34), and a deviation A between the target temperatures TRa and TFa and the actual interior temperatures TR and TF is calculated and accumulated (temperature deviation calculating means 56 and 56). function of the temperature deviation accumulated value calculator 70: step S 3 5). In step S36, the cumulative value A is compared with the upper limit value L_UP and the lower limit value L_DOWN, and the rotational speed of the inverter motor is increased or decreased (function of the rotational speed control means 60: steps S36 to S38).

According to the third embodiment, for example, the temporal changes of the target temperatures TFa and TRa of the refrigerating room 13R and the freezing room 13F during the pull-down cooling operation are set as shown by a dashed line in FIG. Assuming that the actual internal temperature TF, TR of the refrigerator compartment 13R and the freezer compartment 13F has changed as indicated by the solid line, for example, the internal temperature of the refrigerator compartment 13R is compared with the target temperature Tra at the beginning of the cooling operation. The temperature is cooled so that TR becomes lower, and on the freezer compartment 13F side, the internal temperature TF is cooled so as to be substantially equal to the target temperature TFa. Therefore, the total temperature deviation becomes negative, and the accumulated value A is also Become negative. Here, the graph of the accumulated value A becomes sawtooth waveform is because the accumulated value A is initialized at every predetermined time (FIG. 9 step S 3 9). And since the cumulative value A becomes negative and falls below the lower limit L_DOWN, the inverter frequency is gradually lowered at the beginning, and as a result, the rotational speed of the compressor 20 is lowered step by step, and the cooling capacity is suppressed. The inside temperature approaches the degree of decrease in the target temperature.

  If the internal temperature exceeds the target temperature as a result of the reduced cooling capacity, the temperature deviations of the freezing room 13F and the refrigerating room 13R and their accumulated values A change to positive, and the total accumulated value A becomes the upper limit value L_UP. When the pressure exceeds the value, the compressor rotational speed is increased to increase the cooling capacity, and the internal temperature again approaches the degree of decrease in the target temperature. Hereinafter, by repeating such control, the internal temperature decreases in accordance with the temporal change mode of the set target temperature.

  And even if the heat insulation door of the storage main body 10 is temporarily opened during the pull-down cooling operation as described above and the internal temperature temporarily rises due to the flow of outside air, the temperature rise is insulated. As the door is closed, it is rapidly restored, so as long as the accumulated value A of the temperature deviation is observed, there is no sudden change in the accumulated value A. For this reason, the controller 50 does not react sensitively and does not rapidly increase the rotational speed of the compressor 20, so that the control is stabilized, which contributes to power saving.

  In the above description, the pull-down cooling operation is described. However, the upper and lower limits are set above and below the set temperature even in the control operation for cooling the stored product such as food to the set temperature set by the user. The change mode of the target temperature indicating how to change the internal temperature from the upper limit value to the lower limit value in terms of time is functionalized and stored in the storage means, in the same manner as in the pull-down cooling operation. The rotational speed of the compressor is controlled. Therefore, even during the control operation, it does not react sensitively to a temporary sudden change in the internal temperature due to the opening and closing of the heat insulating door, and power saving can be achieved. Further, since the compressor 20 is controlled so as to follow the stored target temperature change mode, the operation stop time of the compressor 20 can be ensured appropriately and each of the coolers 27F and 27R. It is possible to prevent a large amount of frost from being exhibited by exhibiting a kind of defrosting function.

  In commercial refrigerators, the above-mentioned pull-down cooling operation is not limited to the initial installation of the refrigerator, but is a rerun after a few hours have passed since turning off the power, and a long time when carrying a large amount of food. This is necessary even when the door is opened for a long time or when a large amount of high-temperature food is put in immediately after cooking, and its cooling characteristics are extremely important. In view of that point, in the present embodiment, the cooling characteristics during the pull-down cooling operation are not simply given as the final target value of the temperature, but are given as a change with time of the target temperature. A common refrigeration unit can be used for the insulated storage.

  In addition, in the present embodiment, since the target temperature is given as the target temperature for every predetermined time when the target temperature is given as the change mode with time, for example, compared with the case where the target temperature is given as the rate of change in temperature every predetermined time, 1 There is an advantage that it is suitable for a cooling storage type in which the refrigerant from the compressor 20 is supplied alternately to the two coolers 27F and 27R to cool the two chambers. That is, if the cooling target is given as the rate of change in temperature every predetermined time and the rotation speed of the compressor 20 is controlled so as to approach the rate of change, one of the types in which cooling is performed alternately is cooled. While the door of the other storage room is temporarily opened and the internal temperature rises, for example, the internal temperature decreases as soon as the door is closed and the storage room is cooled. The target rate of change for the cooling operation is achieved. For this reason, although the internal temperature actually rises slightly, the rotational speed of the compressor 20 is reduced, and when such a situation is returned, the internal temperature is as expected. Can not be lowered.

  On the other hand, in this embodiment, since the temporal change mode of the target temperature is given as a target temperature that is different (slowly decreases) every predetermined time, there is a temporary rise in the internal temperature. In this case, if the target temperature cannot be reached at that time, the number of revolutions of the compressor 20 is increased and the cooling capacity is increased, so that the internal temperature can be reliably lowered as set.

<Embodiment 4>
As described above, in each of the above-described embodiments, when a large thermal load is accommodated in any one of the storage chambers, the amount of refrigerant supplied to the storage chamber immediately increases to cool the storage chamber with a large thermal load. Is promoted. This means that the cooling capacity of the other storage room is lowered, and there is a concern that the internal temperature of the storage room will rise. For example, in the case of a refrigerator-freezer, if a large load is accommodated in the refrigerator compartment and the cooling time ratio of the refrigerator compartment is unilaterally increased, the frozen food contained in the refrigerator compartment is maintained in a frozen state depending on usage conditions. It may not be possible.

Therefore, in the fourth embodiment, when the valve control means 58 increases the open ratio of the refrigerant supply path of one storage chamber, the temperature inside the storage chamber of the other storage chamber is higher than the set temperature by a predetermined value. It was on condition that it was in the range (embodiment of invention of claim 3 ). Furthermore, in that case, more stable control is enabled on the condition that the state in which the inside temperature of the one storage room is higher than the set value by a predetermined value or more continues for a predetermined time (claim). Embodiment of 4 invention). Except for the valve control means 58, the configuration is exactly the same as in the third embodiment.

  Next, the characteristic operation of the valve control means 58 in the fourth embodiment will be described in detail with reference to FIGS. 11 to 13.

  The temperature deviation calculating means 56, the inter-room temperature deviation integrating means 57, the temperature deviation accumulated value calculating means 70, and the rotational speed control means 60 function in the same manner as in the third embodiment, and the rotational speed of the compressor 20 and the three-way valve 24. Open / close control operates as described above. On the other hand, in the fourth embodiment, the “cooling load determination control” shown in FIG. 11 is also started (step S41). When this “cooling load determination control” is started, first, “R room F room cooling time control” is started as in step S42. This is the process shown in FIG. 4, which is executed simultaneously with the “cooling load determination control” of FIG.

  Next, the process proceeds to step S43, where the process of “R chamber internal temperature determination” is executed, and the internal temperature TR of the refrigerator compartment 13R is a temperature obtained by adding a predetermined value (for example, 2 ° C.) to the set temperature TRa. It is determined whether or not the above state has continued for a predetermined time (for example, 5 minutes). If the condition is not satisfied, the process proceeds to the next step S44. Furthermore, the processing of “F chamber internal temperature determination” is executed, and the state where the internal temperature TF of the freezer compartment 13F is equal to or higher than a temperature obtained by adding a predetermined value (for example, 2 ° C.) to the set temperature TFa for a predetermined time (for example, It is determined whether the process has continued for 5 minutes. If the condition is not satisfied, the process returns to the previous step S43, and steps S43 to S44 are repeated.

  In such a state, it is assumed that, for example, a relatively large thermal load (warm food or the like) is accommodated in the refrigerator compartment 13R. Then, the internal temperature of the refrigerator compartment 13R rises and continues for a relatively long time. Therefore, when the state 2 ° C. or more higher than the set temperature TRa continues for 5 minutes or more, the process proceeds from step S43 to step S45. “F temperature maintenance cooling time control” is started. This content is as shown in FIG. 12. First, the three-way valve 24 waits until the first refrigerant flow path 25F for the freezer compartment 13F is opened (F circuit open) (step S51), and the F circuit is opened. Then, the process proceeds to step S52 to start time calculation for determining whether or not one cycle of “R room F room cooling time control” (see FIG. 3) is completed. “Y” in step S53), “F room temperature determination” is performed (step S54). In this “F room temperature determination”, the internal temperature TF of the freezer compartment 13F is set to a predetermined value α (for example, a temperature corresponding to the difference between the average value of the internal temperature TF and the maximum value) to the set temperature TFa. Judge whether the temperature is higher or lower than the applied temperature. If TF> TFa + α, it can be determined that the internal temperature of the freezer compartment 13F has risen too much and the cooling capacity directed to the freezer compartment 13F is insufficient, so the R cooling time ratio is lowered by one step (step S55). . On the other hand, if TF <TFa + α, the temperature inside the freezer compartment 13F does not increase so much and the cooling capacity directed to the freezer compartment 13F can be determined to be excessive, so the R cooling time ratio is increased by one step (step S56). Otherwise (ie, TF = TFa + α), the R cooling time ratio is not changed and the process returns to step S52, and the above-mentioned "F room temperature determination" is repeated for each cycle. As a result, the refrigerator compartment 13R is cooled by the priority distribution of the cooling capacity to the refrigerator compartment 13R while considering the temperature rise of the freezer compartment 13F under the “F temperature maintenance cooling time control”. The internal temperature TR of the refrigerator compartment 13R and thus the newly introduced food is cooled to the set temperature of the refrigerator compartment 13R. Therefore, even if food having a high temperature is stored in the refrigerator compartment 13R, the cooling capacity is not unilaterally supplied for the cooling, and the temperature TF in the freezer compartment 13F does not exceed TFa + α. Therefore, it is possible to reliably prevent the frozen food 13F from being inadvertently raised and the frozen food being thawed.

  And while such “F temperature maintenance cooling time control” is being executed, “R chamber internal temperature return determination” is performed simultaneously (step S46 in FIG. 11). When the temperature TR becomes lower than the set temperature TRa, the process proceeds to step S47 and the first "R room F room cooling time control" is resumed.

Conversely, if a relatively large thermal load (warm food or the like) is accommodated in the freezer compartment 13F, the internal temperature TF of the freezer compartment 13F rises and continues for a relatively long time. When the state 2 ° C. or more higher than T Fa continues for 5 minutes or more, the routine proceeds from step S44 to step S48, where “R temperature maintenance cooling time control” is started. This content is as shown in FIG. 13, and the principle is the same as the above-mentioned “F temperature maintenance cooling time control”. That is, the internal temperature TR of the refrigerator compartment 13R is larger than the temperature obtained by adding a predetermined value α (for example, a temperature corresponding to the difference between the average value of the internal temperature TR and the maximum value) to the set temperature TRa. If TR> TRa + α, it can be determined that the internal temperature TR of the refrigerating room 13R is excessively high and the cooling capacity directed to the refrigerating room 13R is insufficient. In contrast, if T R <TRA + α, the temperature inside the refrigerating room 13R does not increase so much and the cooling capacity directed to the refrigerating room 13R can be determined to be excessive. Only steps are lowered.

As a result, while giving consideration to the temperature rise of the refrigerating compartment 13R, ing to the freezing room 13F is gradually cooled by priority allocation of cooling capacity of the freezing room 13F. Therefore, even if food with a high temperature is stored in the freezer compartment 13F, the cooling capacity is not unilaterally supplied for cooling, but the temperature TR in the refrigerator compartment 13R does not exceed TRa + α. Therefore, it is possible to reliably prevent the temperature of the refrigerating chamber 13R from inadvertently rising.

  In addition, this invention is not limited to embodiment described with the said description and drawing, For example, the following embodiment is also contained in the technical scope of this invention.

  (1) In the above-described embodiment, the cooling storage room including the freezing room and the refrigerating room has been described as an example. However, the present invention is not limited to this. It may be applied to the cooling storage provided, in short, in the cooling storage provided with storage chambers with different thermal loads, refrigerant is supplied from the common compressor to the evaporator provided in each storage chamber Can be widely applied to.

  (2) In each of the above embodiments, the deviation between the target temperature and the internal temperature is calculated and integrated every predetermined time, and when the integrated value exceeds a predetermined reference value, the rotation speed of the compressor is immediately set. However, other conditions may be taken into account when determining the rotational speed of the compressor.

  (3) In the third embodiment, the target temperature setter 80 stores a function representing the temporal change mode of the target temperature in the storage unit 81, and the function stored in the storage unit 81 is read out to match the passage of time. However, the present invention is not limited to this. For example, as shown in FIG. 14, a reference table in which the temporal change mode of the target temperature is compared with the elapsed time is created in advance. The reference table may be stored in the storage unit 100, and the target temperature in the storage unit 100 may be read as the time elapses by the table reading unit 101 in accordance with a signal from the timing unit 102.

1 is an overall cross-sectional view showing Embodiment 1 of the present invention. Refrigeration cycle configuration diagram and block diagram of Embodiment 1 The flowchart which shows the cooling operation of Embodiment 1. The flowchart which shows the cooling operation of Embodiment 1. In Embodiment 2, the graph which shows the temperature change when the cooling capacity is insufficient In Embodiment 2, the graph which shows the temperature change when cooling capacity is excessive Refrigeration cycle block diagram and block diagram of Embodiment 3 The graph which shows the time-dependent change aspect of the target temperature of the freezer compartment and refrigerator compartment in Embodiment 3. 10 is a flowchart showing a control procedure of the compressor rotation speed in the third embodiment. The graph which shows the relationship between the change aspect of the chamber temperature at the time of pull-down cooling operation in Embodiment 3, and a compressor rotation speed The flowchart which shows the process sequence of the "cooling load determination control" in Embodiment 4. The flowchart which shows the process sequence of "F temperature maintenance cooling time control" in Embodiment 4. The flowchart which shows the process sequence of "R temperature maintenance cooling time control" in Embodiment 4. The block diagram which shows other embodiment which varied the target temperature setting means

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Storage body 20 ... Compressor 21 ... Condenser 24 ... Three-way valve (valve device) 25F, 25R ... First and second refrigerant supply paths 26F, 26R ... Capillary tube (throttle device) 27F ... Freezer compartment evaporator (First evaporator) 27R ... Refrigerating room evaporator (second evaporator) 31 ... Refrigerant circulation channel 40 ... Refrigeration cycle 50 ... Refrigeration cycle control circuit 51F ... Temperature sensor (first temperature sensor) 51R ... Temperature Sensors (second temperature sensors) 55, 80 ... target temperature setter 56 ... temperature deviation calculating means 57 ... inter-room temperature deviation integrating means 58 ... valve control means 60 ... rotation speed control means 70 ... temperature deviation accumulated value calculating means 81 ... Storage means 100 ... Storage means 101 ... Table reading means 102 ... Time measuring means

Claims (7)

A refrigeration cycle having the following configurations A1 to A6;
(A1) Compressor for compressing refrigerant
(A2) A condenser that releases heat from the refrigerant compressed by the compressor
(A3) The inlet is connected to the condenser side, the two outlets are connected to the first and second refrigerant supply paths, and the inlet side is selected as one of the first and second refrigerant supply paths Device that enables flow switching operation that allows continuous communication
(A4) First and second evaporators provided in the first and second refrigerant supply paths, respectively.
(A5) A throttling device for throttling the refrigerant flowing into each of the evaporators
(A6) Refrigerant ring passage connected from the refrigerant outlet side of the first and second evaporators to the refrigerant suction side of the compressor
A storage body having first and second storage chambers that have different thermal loads and are cooled by the cold air generated by the first and second evaporators;
A target temperature setter for setting a target temperature in each of the first and second storage chambers;
First and second temperature sensors for detecting the internal temperature of each storage chamber;
A temperature deviation that is a difference between each target temperature of each storage chamber set in the target temperature setter and the internal temperature of each storage chamber detected by each temperature sensor is calculated for each storage chamber. Temperature deviation calculating means;
Inter-room temperature deviation integrating means for calculating an inter-room temperature deviation which is a difference for each storage room with respect to the temperature deviation calculated by the temperature deviation calculating means,
A cooling storage comprising: valve control means for changing the open ratio of each of the first and second refrigerant supply paths in the valve device by comparing the integrated value integrated by the inter-room temperature deviation integrating means with a reference value . The compressor is driven by an inverter motor,
  A temperature deviation cumulative value calculating means for calculating a temperature deviation cumulative value that is a cumulative value of the sum for each storage room with respect to the temperature deviation calculated by the temperature deviation calculating means;
  The cooling storage according to claim 1, further comprising: a rotational speed control means for changing the rotational speed of the inverter motor by comparing the cumulative value calculated by the temperature deviation cumulative value calculating means with a reference value. In the case where the opening ratio of the refrigerant supply path of one storage chamber is increased, the valve control means is provided on the condition that the internal temperature of the other storage chamber is within a temperature range higher than the set temperature by a predetermined value. The cooling storage of Claim 1 or Claim 2 to do. When the valve control means increases the open ratio of the refrigerant supply path of one storage chamber, the internal temperature of the one storage chamber continues to be higher than the set temperature by a predetermined value. The cooling storage of Claim 3 which is on condition that it exists above . The cooling storage according to any one of claims 1 to 4, wherein the target temperature setter is configured to sequentially output different target temperatures over time . The target temperature setter includes a storage unit that stores a function that represents a temporal change mode of the target temperature, and a target temperature calculation that reads the function stored in the storage unit and calculates the target temperature as time elapses. The cooling storage according to claim 5, comprising means . The target temperature setter stores storage means as a reference table in which the temporal change mode of the target temperature is contrasted between temperature and elapsed time, and table reading means for reading out the target temperature in the storage means as time elapses The cooling storage of Claim 5 provided with these .

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